CHEMICAL ENGINEERING

MASS TRANSFER 275 The rising velocity is given by a force balance: 3 d 1 uD^16 d^31 + 1 + 2 g or: u 1 D d^21 g 18  + 1  ...

276 CHEMICAL ENGINEERING VOLUME 1 SOLUTIONS Case2: diameterD 0. 9 dDd 2 , Q 2 D 1. 25 Q 1 The number of drops per unit time is: ...

MASS TRANSFER 277 Solution For a binary system, Maxwell’s Law gives:  dCA dy DFCACBuAuB (equation 10.77) For an ideal gas mix ...

278 CHEMICAL ENGINEERING VOLUME 1 SOLUTIONS Comparing equations (iii) and (iv), then: 1 D^0 D 1 CTCA { CB DAB C CC DAC C... } D ...

MASS TRANSFER 279 Thus: CADCT 0. 25  0 D 0. 25 CT CBmD 1  0. 75 ln 0.^175 CTD 0. 869 CT CT CBm D 1. 150 and the mass transfe ...

280 CHEMICAL ENGINEERING VOLUME 1 SOLUTIONS The average mass transfer rate is: 1 te { 2 √ D  CAt^1 e/^2 } D 2 √ D te CA In t ...

MASS TRANSFER 281 Fraction of surface of age 0 to 1 s DK ∫ 1 /s 0 estdtDK [ est s ] 1 /s 0 D K s  1 e^1 Fraction of surfac ...

282 CHEMICAL ENGINEERING VOLUME 1 SOLUTIONS The mass transfer coefficienthDis proportional to the velocity raised to the power o ...

MASS TRANSFER 283 0. 260 ð 106 C 1 hD D 0. 312 ð 106 C 0. 792 1 hD 1 hD D 0. 25 ð 106 and:hDD 4. 0 ð 10 ^6 m/s. PROBLEM 10.47 E ...

284 CHEMICAL ENGINEERING VOLUME 1 SOLUTIONS CTD P RT D  0. 760 ð 13 , 600 ð 9. 81  8314 ð 349 D 0 .0350 kmol/m^3 For air: CB ...

SECTION 11 The Boundary Layer PROBLEM 11.1 Calculate the thickness of the boundary layer at a distance of 75 mm from the leading ...

286 CHEMICAL ENGINEERING VOLUME 1 SOLUTIONS PROBLEM 11.2 Water flows at a velocity of 1 m/s over a plane surface 0.6 m wide and ...

THE BOUNDARY LAYER 287 Solution The shear stress in the fluid at the surface:RD ux/y From the equation given: RD 0. 03 u^2 ...

288 CHEMICAL ENGINEERING VOLUME 1 SOLUTIONS Solution The derivation of the momentum equation for an element of the boundary laye ...

THE BOUNDARY LAYER 289 PROBLEM 11.7 Explain the concepts of “momentum thickness” and “displacement thickness” for the boundary l ...

290 CHEMICAL ENGINEERING VOLUME 1 SOLUTIONS Thus, putting D υt/υ, the heat flow becomes: QDusTsCpυ [∫x 0 2. 25 y/υ^2 /  0. ...

THE BOUNDARY LAYER 291 ∴ ∫υ 0 u^2 ydyDu^2 s υυm and: ∫υ 0 uydyDus υυŁ ∫ 1 0 uy/us 2 d y/υD 1  υmυ and: ∫ 1 0 uy/us d y/ ...

292 CHEMICAL ENGINEERING VOLUME 1 SOLUTIONS If the velocity within the boundary layer may be represented by a sine function: ux ...

THE BOUNDARY LAYER 293 Solution The derivation of the momentum equation is given in Section 11.2 to give:  ∂ ∂x ∫l 0 ux usux d ...

294 CHEMICAL ENGINEERING VOLUME 1 SOLUTIONS PROBLEM 11.11 Derive the momentum equation for the flow of a fluid over a plane surf ...